Obesity is reaching epidemic proportion in the United States with recent surveys showing that over half of all U.S. adults are overweight or obese. Obesity is difficult and treat and relatively few individuals are successful at long-term maintenance of weight loss. These facts make prevention of obesity an important goal. The present application targets the prevention of pregnancy-associated obesity in African-American women. Pregnancy is a high-risk time for the development of obesity. The average weight retention after pregnancy is 2-5 pounds but many women retain considerably more weight postpartum. Previous studies have shown that African-American women retain more weight following pregnancy than Caucasians and are less likely to diet to loss the excess pregnancy weight. African-American women have a higher rate of obesity than Caucasians, and the role of pregnancy in the obesity of this population is unknown. The present application describes a randomized, controlled, parallel-arm intervention study in postpartum African-American women. The overall goal of the present proposal is to evaluate the effectiveness of traditional versus Internet-aided behavior modification for weight management in postpartum African-American women. The Internet-based intervention will be used in addition to face-to-face group sessions to allow for more extensive behavioral feedback and contact with interventionists. Thus, this proposal makes use of innovative technology in the prevention of obesity in a population at extremely high risk for excess weight gain. The research will address the primary hypothesis that the use of the Internet-aided behavior intervention will be more effective than traditional behavioral intervention program in preventing excess postpartum weight retention. Fifty-six previously non-obese postpartum women who retained > 25 pounds of excess weight after pregnancy will be studied in this pilot program. All subjects will receive 12 bimonthly group sessions providing core information on healthy diet, activity, and weight loss. Half the subjects will be assigned to an experimental arm involving an Internet-aided behavioral modification to supplement group sessions. The Internet intervention will continue for 3 months past the core group intervention for a total of 9 months of intervention. The control group will receive only the group sessions. This application addresses a critical gap in our knowledge of effective obesity preention strategies in African-American women, a group at high risk for obesity. In addition, these studies allow us to address ways of preventing the development of obesity following pregnancy, which has relevance to all women.